High oxidizing activity of 3,10-dimethyl-8-azaisoalloxazine (8-azaflavin) and its synthetic application as a turnover redox catalyst under aerobic conditions

Abstract

8-Azaflavin (1) has been synthesized, and its oxidizing activity has been examined kinetically for the oxidation of N-benzyl-1,4-dihydronicotinamide (BNAH), thiols, and nitroalkanes in aqueous solution under anaerobic conditions, by means of a comparison with 3,10-dimethylisoalloxazine (2). It was found that (1) is much more reactive than (2), 41 -fold for BNAH, and 10⁴–10⁶-fold for thiols; (1) can be used as a turnover oxidation–reduction catalyst for disulphide and aldehyde syntheses in aqueous solution under aerobic conditions. The hydrolysis of (1) and the reducing activity of the reduced (1) have been briefly examined.